Ataxia Telangiectasia affects 1 in every 40,000 to 1 in 100,000 people around the world. It has no inclination towards a particular race or region and affects both men and women without any preference to either. A-T, as it is called, is an unusual syndrome that commences in the childhood and affects many organs of the body, particularly the brain which leaves a patient severely disabled. Even before the kids are diagnosed of this disease, they die of the disease and thus, it is prevalent, more than it is expected.
The name, Ataxia Telangiectasia, is formed by two terms – Ataxia means uncoordinated movements while Telangiectasia refers to the enlarged blood vessels right underneath the skin surface. It’s pronunciation in English is “At-uck-seahtay-lan-giak-tasia”. The condition is also known as A-T, ATM, Louis-Bar Syndrome and Boder-Sedgwick Syndrome.
Types of Ataxia Telangiectasia
A-T has been classified into 4 categories: Type I, Type II, Type III and Type IV.
- Type I: This one is the typical form – the patients suffer from most or all the symptoms.
- Type II: In Type II, instead of the clinical findings, the patients seem to be sensitive to radiation.
- Type III: In Type III, patients are not sensitive towards radiation but have other diagnosed symptoms.
- Type IV: Some of the condition’s symptoms are exhibited and he’s not radiation sensitive.
Symptoms of Ataxia Telangiectasia
A-T is known to damage the cerebellum, a part of your brain that is responsible for motor coordination in the body. Furthermore, the immune system is impacted which in turn causes respiratory problems and increases the chances of getting cancer. It is a condition that onsets in childhood itself and toddlers do exhibit signs initially. These include slurred speech, poor balance, delayed walking, less coordinated movements, jerky gait, vulnerability to infections, discolored skin patches and delayed motor skills development which eventually stops after a decade. These symptoms come up in the first decade while in later years, the victim gets other symptoms like Telangiectasia’s which is arrival of small red spider like veins on nose, ears, cheeks, inner side of elbows and knees. Besides these, seizures, sensitivity to radiations, abnormal eye movements, respiratory infections and inflammation of capillaries in eyes are some of the other symptoms that appear late.
Sufferers also have high protein levels in their blood, especially in pregnant ladies. As a matter of fact, kids with A-T don’t generally have mental disabilities – intelligence level is normal in most of the kids.
Causes of Ataxia Telangiectasia
ATM gene mutation causes A-T. ATM gene has many roles in the body – it detects and corrects faults in duplication of DNA during cell division and destroys the cells in case it fails to correct the faults; it repairs the breaks in double-stranded DNA and it is also responsible for encoding a kinanse for p53 action. Moreover, body needs it for normal growth as well as for functioning of several systems like nervous system and immune system. So when mutation in ATM gene is caused, the functions it performs get eliminated or in some cases, reduced. In its absence, the cell die prematurely and the ones in the cerebellum are particular affected. For cerebellum controls the movements, its dysfunction results in disabilities in movements. Because DNA damages don’t appear owing to these mutations, the DNA breaks get accumulated and may even develop cancerous tumors.
It is a genetic defect that is inherited by the kid if both his parents have mutated ATM gene. Although in some cases, children don’t get the disease even if both the parents carry the gene.
Carriers of Ataxia Telangiectasia
In genetics, carrier is someone who has a normal and one mutated copy of ATM gene. Normally, such people don’t show severe symptoms or any symptom at all of A-T and thus, they are mostly unaware that they are carriers. Still, the risk of them developing breast cancer is 16 times more and they die about 7-8 years early than their healthy counterparts – heart diseases are often the cause. By the time they reach 70 years, 60% of people supposedly carry the mutated gene.
In US, about 1% of the total population or 2.5million people are the carriers of A-T.
Treatment& Diagnosis of Ataxia Telangiectasia
Ataxia Telangiectasia is diagnosed when the kid who is suffering from uncoordinated movements or ataxia develops Telangiectasia, arrival of red veins on nose, cheeks and corner of eyes. While diagnosing this disease, the doctors look for physical signs such as decreased physical development, changes in skin texture and color, undersized spleen, retarded sexual development, and mask-like face appearance.
The diagnostic exams for this condition includes: glucose tolerance test, carcinoembryonic antigen, alpha fetoprotein, x-ray, B & T cell screen, genetic testing. Meanwhile, the physicians also differentiate from other conditions with similar symptoms like the Refsum disease, Hartnup disease, Cerebral palsy, Ataxia oculomotor apraxia type 1, Niemann-Pick disease, Ataxia oculomotor apraxia type 2, Nijmegen breakage syndrome and Gaucher disease.
Ataxia Telangiectasia is incurable. The treatment is symptomatic and the underlying cause is not addressed. Doctors give gamma-gobulin shots to the kids to increase their immunity and extra vitamin doses are also administered. A healthy immune system can help the body fight the problems that develop due to it. In case a patient develops cancer, parents might subject the kid to chemotherapy but in most cases, the patients are sensitive to radiation and consequently, radiation therapy is not directed. Even X-rays are not very frequently done for the immunity is already low and the radiation might deteriorate the condition even further. Sufferers are sensitive to X-rays especially – the blood cells lose their ability to duplicate and form cell colonies after they are exposed to X-rays. Physical therapy, speech therapy and occupational therapy might also be needed.
Life expectancy depends from a person to another. People survive into adulthood with this syndrome but life expectancy is reduced generally and early death is very common among patients of A-T. A good percentage of patients die in early 20’s or in teen years.
Complications & Prevention of Ataxia Telangiectasia
Patients with the condition are prone to severe lung infections because of a weak immune system. A-T causes a lot of complications, malignant conditions like Leukemia, breast cancer and Lymphoma. Additionally, there are increased risks of diabetes, Kyphosis, Scoliosis, heart diseases, lung infections and movement disorder which could make the patient wheel-chair bound later.
As there is no cure to the condition, there is also no way to prevent it. The only thing people can do is go for genetic counseling if there is history of this condition in the family. Genetic counseling can help them determine if their partners are carriers of the mutated gene. Parents with the kids having A-T have high risk of developing cancer and have to consider serious cancer screenings also. Family members of Heterozygote should also monitor for cancer regularly.